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Raúl Pérez-Ruiz Robert Fichtler Yrene Diaz Miara Matthieu Nicoul Dominik Schaniel Helfried Neumann Matthias Beller Dirk Blunk Axel G. Griesbeck Axel Jacobi von Wangelin 《Journal of fluorescence》2010,20(3):657-664
The photophysical properties of a series of structurally related 4-aminophthalimides and the corresponding 5-aminophthalic
hydrazides (luminols) are reported. Absorption, steady-state, and time-resolved fluorescence spectra of luminols exhibited
substitution, solvent, and pH dependence. Singlet lifetimes have been determined by time-resolved laser flash spectroscopy.
UV spectra in gas phase and DMSO solution were calculated by TD-DFT which revealed the existence of two low-energy excited
singlet states with strong pH-sensitivity. 相似文献
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Mingfu Zhang Axel H. E. Müller 《Journal of polymer science. Part A, Polymer chemistry》2005,43(16):3461-3481
In recent years, research on cylindrical polymer brushes (or molecular bottlebrushes) has received significant attention. In this article, we discuss various strategies for their synthesis and the unique properties arising from their regular multibranched structure. Some recent advances in the application of cylindrical polymer brushes are highlighted. Amphiphilic core– shell cylindrical polymer brushes, for example, have been successfully used as single molecular templates for inorganic nanoparticle formation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3461–3481, 2005 相似文献
118.
Squalene-hopene cyclase (SHC) catalyzes the conversion of squalene into pentacyclic compounds. It is the prokaryotic counterpart of the eukaryotic oxidosqualene cyclase (OSC) that catalyzes the steroid scaffold formation. Because of clear sequence homology, SHC can serve as a model for OSC, which is an attractive target for anticholesteremic drugs. We have established the crystal structure of SHC complexed with Ro48-8071, a potent inhibitor of OSC and therefore of cholesterol biosynthesis. Ro48-8071 is bound in the active-center cavity of SHC and extends into the channel that connects the cavity with the membrane. The binding site of Ro48-8071 is largely identical with the expected site of squalene; it differs from a previous model based on photoaffinity labeling. The knowledge of the inhibitor binding mode in SHC is likely to help develop more potent inhibitors for OSC. 相似文献
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A solvent-free photooxygenation process that uses organic substrates embedded in porphyrin-loaded polystyrene beads as solid support is described and applied for ene- and [4 + 2]-cycloaddition reactions involving singlet oxygen (1 delta g). 相似文献
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A sequence of single photons is emitted on demand from a single three-level atom strongly coupled to a high-finesse optical cavity. The photons are generated by an adiabatically driven stimulated Raman transition between two atomic ground states, with the vacuum field of the cavity stimulating one branch of the transition, and laser pulses deterministically driving the other branch. This process is unitary and therefore intrinsically reversible, which is essential for quantum communication and networking, and the photons should be appropriate for all-optical quantum information processing. 相似文献